Tamper evident caps for containers, such as blow-molded or injection molded containers are well known, see e.g., U.S. Pat. Nos. 4,561,553, 4,625,875, 4,497,765, and 4,534,480. A number of caps are of the snap-on screw-off variety such as U.S. Pat. Nos. 5,553,727, 5,190,178, 5,213,224, 5,267,661, 5,285,912, 5,480,045, 5,456,376, and 5,307,946 and 5,560,504. Generally, the prior art caps include a spiral thread or threads which match a spiral thread on the neck of the bottle. In U.S. Pat. No. 5,307,946 the cap and bottle neck include a seven lead-in end annular spiral thread configuration (or fastening means) and in U.S. Pat. No. 5,553,727 the cap and bottle neck include a ten lead-in end annular spiral thread configuration (or fastening means). The advantage of the multiple lead-in threads is the increased ease of "snap-on" placement of the cap onto the threaded neck using standard bottle capping equipment and without an additional tightening step such as a final twist.
As is apparent from the prior art patents, a great deal of effort has gone into design of cap and bottle neck configurations to provide easy on and off use of the cap by the bottler and ultimately by the end user of the bottled product. However, notwithstanding this effort, the bottling industry continues to search for a cap and neck finish which achieves these objectives but which also provides a secure seal.
The present invention solves this problem by optionally providing at least one annular sealing bead depending from the outer surface of the closure valve which are compressed against the inner surface of the container neck to form a seal as the closure is snapped onto the container neck. Optionally, sealing engagement between the closure and the mating portions of the exterior wall of the container neck may be further improved by including one or more annular sealing beads on the interior surface of the closure depending annular skirt.
The present invention also solves the problem of protecting the integrity of frangible elements during installation of threaded tamper-evident closures. A plurality of elevated areas extend upwardly from the tamper-evident band in spaced relation to the bottom edge of the closure body. The purpose of these elevated areas is to support the tamper evident band in resisting vertical movement imparted by insertion of the closure on the bottle neck, thereby protecting the frangible elements during assembly. The frangible elements connecting the tamper-evident band to the lower edge of the closure body may be configured to extend from these elevated areas as well as the non-elevated areas of the tamper-evident band. The purpose of attaching frangible elements to the elevated areas of the tamper-evident band is to assist in preventing axial misalignment of the tamper-evident band relative to the annular depending skirt portion of the closure upon subjecting the closure to torquing forces during assembly to the container neck.
At least one and preferably a plurality of circumferentially spaced lugs optionally extend from the exterior wall of the container neck. These lugs facilitate breaking the frangible elements on the tamper-evident band of the closure by engaging the frangible elements as the closure is twisted off the container neck following initial snap-on application.
Additionally, the tamper indicating closure may include at least one arcuate projection extending around at least a portion of the tamper indicating ring arranged for registration with an annular locking flange on a container neck portion on which the closure is positioned. The closure is provided with at least one member attached to the tamper-indicating ring which cooperates with the arcuate projection to assist in breaking the tamper indicating ring during removal of the closure from the container neck. The arcuate projection is held in place by the locking flange on the container neck as the member is pulled away from the arcuate projection during twist-off removal of the closure body to cause the tamper indicating ring to break at a weakened area. Finally, the bottle neck finish may be optionally configured with a recessed area in which the tamper indicating ring of the closure rests. The closure is installed and the tamper indicating ring removed in the same manner as with a non-recessed bottle neck finish, but the recessed configuration improves tamper evidency protection by eliminating the ability to manually pry the closure upwardly from underneath the tamper indicating ring in order to remove the closure from the neck finish without breaking the tamper indicating ring.
Prior art threaded push-pull pour spout closures providing tamper evidency and having tamper evident pour spouts have not always been leak proof at the spout closure interface. Generally, prior art push-pull pour spout closures that are reusable do not provide effective sealing at the juncture between the spout opening and the plug positioned in the opening when the spout is closed. Because of the very small diameter of the opening and the concern for safety, it is not possible to add non-integrated sealing means. The present invention solves this problem by utilizing a closure plug which combines a circular closure disk with an integral annular skirt depending from the periphery of the disk thereby defining a hollow cavity for the plug interior and increasing the structural flexibility of the plug. The increased structural flexibility provided by the hollow cavity causes inward deformation of the plug skirt upon engagement with annular flanges integrated into the periphery of the spout closure central opening to create a form-fitting leak tight seal. A plurality of circumferentially spaced dimples optionally extend from the exterior wall of the pour spout. These dimples facilitate breaking the frangible elements connecting the tamper evident band to the push-pull pour spout closure. Optionally, one or more continuous or discontinuous locking beads on the pour spout can be configured to engage one or more continuous or discontinuous locking beads on the pour spout closure to provide a structure for securing the pour spout closure to the pour spout the closed position and/or to prevent removal of the pour spout closure from the pour spout in the open position.
The present invention also optionally provides a dust cover which encloses the push-pull pour spout closure when inserted on the container. One example of the use of dust covers as a means for sealing containers is shown in U.S. Pat. No. 5,456,374. The dust cover of the present invention is optionally provided with a tamper-evident sealing band which remains intact upon initial installation of the dust cover onto the container and which is broken when the dust cover is initially disturbed. The purpose of the dust cover is to provide an indication of whether the push-pull pour spout closure has been exposed subsequent to the sealing of the container. When the dust cover is provided with a tamper-evident sealing band, the use of a band on the lower edge of the pour spout closure for providing tamper-evidency may be eliminated.
Accordingly, it is an object of the present invention to improve sealing engagement between the closure and the mating portions of the interior wall of the container neck by including at least one annular sealing bead depending from the outer surface of the closure valve which are compressed against the inner surface of the container neck to form a seal as the closure is snapped onto the container neck.
It is a further object of the present invention to improve sealing engagement between the closure and the mating portions of the exterior wall of the container neck by including one or more annular sealing beads on the interior surface of the closure depending annular skirt.
It is a further object of the present invention to provide a lug configuration for facilitating the breakage of frangible elements on the tamper evident band of the closure.
It is a further object of the present invention to provide a threaded tamper-evident closure having frangible elements attached from and between a plurality of elevated areas extending upwardly from the tamper-evident band, for protecting the integrity of frangible elements during installation of the closure on a bottle neck.
It is a further object of the present invention to provide a closure with at least one member attached to the tamper-indicating ring which cooperates with the arcuate projection to assist in breaking the tamper indicating ring during removal of the closure from the container neck.
It is a further object of the present invention to provide a closure and bottle neck finish with a recessed area in which the tamper indicating ring of the closure rests so as to improve tamper evidency protection by eliminating the ability to manually pry the closure upwardly from underneath the tamper indicating ring in order to remove the closure from the neck finish without breaking the tamper indicating ring.
It is a further object of the present invention to provide a threaded tamper-evident closure with a reusable push-pull pour spout having a closure plug of increased structural flexibility to provide a more effective leak tight seal.
It is a further object of the present invention to provide a dimple means for facilitating the breakage of frangible elements on the tamper evident band of the push-pull pour spout closure.
It is a further object of the present invention to provide a threaded tamper-evident closure with a reusable push-pull pour spout that utilizes an upwardly angled hook-shaped annular flange to prevent removal of the closure body from a bottle neck while the tamper evident band remains intact.
It is a further object of the present invention to provide a threaded tamper-evident closure with a reusable push-pull pour spout having a plurality of fins or gussets extending upwardly from and in a direction substantially perpendicular to the sealing surface of an annular hook-shaped flange, to assist in breaking and dislodging the tamper-evident band from the remainder of the closure body.
It is a further object of the present invention to provide frangible elements attached from and between a plurality of elevated areas extending upwardly from the tamper-evident band, for protecting the integrity of frangible elements during installation of the closure on a bottle neck.
It is a further object of the present invention to provide one or more continuous or discontinuous locking beads on the pour spout configured to engage one or more continuous or discontinuous locking beads on the pour spout closure to provide a structure for securing the pour spout closure to the pour spout the closed position and/or to prevent removal of the pour spout closure from the pour spout in the open position.
It is a further object of the present invention to provide a dust cover which encloses the push-pull pour spout closure when inserted on the container.
It is a further object of the present invention to provide a dust cover with a tamper-evident sealing band which encloses the push-pull pour spout closure when inserted on the container.
It is a further object of the present invention to eliminate the need for a band on the lower edge of the pour spout closure to provide tamper-evidency for the pour spout by providing a dust cover with a tamper-evident sealing band which encloses the push-pull pour spout closure when inserted on the container.